I don't get it why Pandaren cannot be DKs

The main reason why they didnt want DK Pandarens is cuz it would destroy the timeline right?
Lich King was First > Than the Pandas...
Well fine :P

But what about those Pandaren who were traveling across the Azeroth?
We can find them in various places...
For instance in Azuremyst Isle where one of the Panda Monks states that he heard an Explosion (which turns out to be the Landing of Exodar)
This event predates LichKing since it was in BC :P
There was alot of wandering Pandaren across Azeroth~!

Guess Blizz had enough resources to create Panda DKs but went the easier way (so that the community wouldn't be raging about it)

Worgen DK's lorewise is not ok: the scourge never reached within Gilneas, so no Dead hero's there. But since Worgens are in nature Humans, Blizzard allowed this.

the scourge did reach gilneas, it just didn't go past the wall. but it did reach Pyrewood village, a gilnean village owned by Darius Crowley (and the reason why he became part of the opposition against graymane after the wall was built). Pyrewood village was much closer to shadowfang keep than the rest of gilneas, and obviously it was infected by the curse of the worgen as well. Worgen Deathknights came from there.

of course, alliance players usually don't know silverpine well, so they they are often oblivious of the existence of Pyrewood village, leading them to the conclusion that worgen deathknights are merely lolore.

I don't get why we have goblin/worgen DKs either. They weren't part of the Third war in the eastern kingdoms. Hell even Taurens/Draenei are a bit iffy, but they could have been turned during early wrath /shrug

I don't think any race that joined after the Light Hope chapel battle should be able to have DKs.

It might have also been a coding thing since they are the first neutral race and the dk starting zone may have had issues with it.

You are the first to think of it that way and from that makes the most sense.

And thus I can see why they never had Pandaren DK's since they start out as a playable neutral race that is allowed choose which side to fight for when you got to that part.. It would not work to well in the DK starting zone for the very reason of them starting out as neutral..

Playable goblins are Bilgewater goblins, we never saw them before, they are not the same as the WCIII goblins, and they never left Kezan before Cataclysm.

goblin DKs are steamwheedle. you see that on the quest where you go talk to an old friend from when you were alive.

Gally Lumpstain says: You don't remember me, <name>? I lost count of the number of jobs you and I ran back in the day on Kezan. Then I picked up a real bad Kaja'Cola habit and you saved me! It was you who took me to Kalimdor to join the Steamwheedle Cartel. You were the only good goblin I knew. That's how I ended up in the Argent Dawn, because I knew it's what you woulda done. How could this have happened to you?

the scourge did reach gilneas, it just didn't go past the wall. but it did reach Pyrewood village, a gilnean village owned by Darius Crowley (and the reason why he became part of the opposition against graymane after the wall was built). Pyrewood village was much closer to shadowfang keep than the rest of gilneas, and obviously it was infected by the curse of the worgen as well. Worgen Deathknights came from there.

of course, alliance players usually don't know silverpine well, so they they are often oblivious of the existence of Pyrewood village, leading them to the conclusion that worgen deathknights are merely lolore.

Correct, and Arthas came by this way personally to dig up Arugal between vanilla and wrath.

A quest in the DK starter zone for both races has you kill an old friend and they added a worgen and goblin who explain it.

Worgen: Escaped from Arugal's torture in Silverpine, one of them died to become the DK the other joined the Argent Dawn shortly afterwards.

Goblin: It is explained by the npc that the Goblin DK and his companion were Steamwheedle cartel members (same Goblins as Everlook, booty bay, Gadgetzan) working for the argent dawn in some capacity killed and raised.